跟谁鼠标移动 

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<style>
#div1 {width: 100px; height: 100px; background: red; position: absolute;}
</style>
<script>
window.onload = function() {
    
    /*
    onmousedown : 选择元素
    onmousemove : 移动元素
    onmouseup     : 释放元素
    */
    var oDiv = document.getElementById('div1');
    oDiv.onmousedown = function(ev) {
        var ev = ev || event;
        var disX = ev.clientX - this.offsetLeft;
        var disY = ev.clientY - this.offsetTop;
        //onmousemove在onmousedown之后，所以可以写在里面。        //不用oDiv.onmousemove是因为防止鼠标移除div就不会有移动事件了，div的鼠标移动会冒泡到document，
        document.onmousemove = function(ev) {
            var ev = ev || event;    
            oDiv.style.left = ev.clientX - disX + 'px';
            oDiv.style.top = ev.clientY - disY + 'px';
        }
        document.onmouseup = function() {
            document.onmousemove = document.onmouseup = null;
        }
    }
}
</script>
</head>

<body>
    <div id="div1">
    </div>
    <div style="width: 100px; height: 100px; background: green; position: absolute; left: 400px; top: 200px;">
    </div>
</body>
</html>

 

posted @ 2016-08-01 22:11  无天666  阅读(189)  评论(0)    收藏  举报